reports

Adaptation of the categories Johns-Hopkins ACG Case-Mix System in primary healthcare: a longitudinal, retrospective claim database study

WebmedCentral ECONOMICS OF MEDICINE 2:WMC001657.

Directorate of Planning, Badalona Serveis Assistencials SA, Badalona, Spain

BACKGROUND: To determine the adaptation capacitating of categories case-mix adjustment (Adjusted Clinical Groups [ACG]) in Primary healthcare (PHC) in function of the cost of care in routine clinical practice.

METHODS/DESIGN: Retrospective study based on computerized medical records. All patients attended by 14 PHC teams in 2009 are included. The principle measurements were: demographic variables (age and sex), dependent variables (costs of care) and case-mix or morbidity (Johns Hopkins University Adjusted Clinical Groups Case-Mix System) variables. Episodes occurring in the study population will be accounted for by the date of registration in the clinical history for each episode/reason for consultation, whether acute or chronic, regardless of the date of initiation of the diagnostic process. ICPC-2 will be converted (mapped) to ICD-9-MC. The costs model for each patient will be established by differentiating the fix costs from the variable costs. Fix-costs: staff (wages and salaries), consumer goods, external services (structure and management); and variable-costs (laboratory, conventional-radiology, diagnostic tests, referrals and prescriptions). In the analysis, the ANOVA, chi-squared, Pearson’s lineal correlation and Mann-Whitney-Wilcoxon tests will be used. The adaptation capacitating of each category was obtained: a) outliers (atypical observations), and b) variation of Pearson coefficient. Predictive model of cost: coefficient of determination (R2) will be measured, p

DISCUSSION: The proliferation of similar studies, with homogenous definition criteria between variables, would favor the possibility of benchmarking between centres and professionals from different organizations.